The present invention is generally related to collapsible shipping containers, and more particularly to a shipping container that can be stacked when empty to improve efficiency and reduce transportation costs and emissions.
For decades the importation of ocean-going sea containers has had a substantial impact on the availability of goods for consumption and manufacturing in the United States and abroad. Unfortunately, the trade lanes have suffered a huge laden volume imbalance where as much as four to five laden containers coming inbound only to realize about one laden container moving outbound. This imbalance is due in part to other countries ability to produce goods at a lower price or receiving subsidies to sell or market their goods to the United States. As a result, the utilization of the container has, for the most part, been one direction. This imbalance means that container lines are paid for the one-way import and are compelled to move or reposition the empty containers back to a foreign port with a significant financial cost to the steamship lines (this cost is in the billions of dollars annually). Transportation intermediaries are essentially moving air (the empty space inside the container) back to the origin foreign port(s) while emitting pollutants as the containers are repositioned back to these origin ports.
The cargo containers in use today have become standardized in dimension and structural, and are such that they can be easily, conveniently and securely stacked vertical in a side by side and end to end relationship to maximize the use of hold and deck space on ships and the like, on which such containers are placed. Trailers are standardized to carry the containers for delivery by trucks and the like.
The principal shortcoming found in the use of these cargo containers, as cited above, resides in the fact that day to day commerce can require that these containers be transported empty from a station or site of delivery of cargo to a next site or station for receipt or loading of cargo. Such transporting of empty containers is non-profitable since each such container occupies valuable and costly space on the ship that could otherwise accommodate a loaded or filled container. Further, the handling and shipping of both loaded and empty containers creates a multitude of other problems. One such problem resides in arranging light, empty containers and heavy, loaded containers aboard ships in such a manner that the ships are properly and safely trimmed.
When transporting a high percentage of empty containers, the voyage of such ships is uneconomical and must be made up somewhere along the way with increased costs of goods and shipping. Accordingly, large economic savings in shipping by containers could be realized if empty containers could be folded or collapsed so that they occupy a fraction of the space they occupy when in their expanded configuration. For example, if three or more containers when collapsed could occupy the space of one container in its normal configuration, the cost of shipping empty collapsed containers would be dramatically reduced.
The prior art has proposed a number of nesting cargo container structures intended to effectively reduce the space required for their shipment when they are empty. While certain proposed nesting containers might well serve such an end, it is understood that they are seriously wanting in certain material respects. For example, a shortcoming found in space saving cargo containers proposed by the prior art includes the deconstruction of the container with the resultant burden of removable or separable parts which are subject to being misplaced, lost, damaged and/or stolen. Experience has taught that if parts of equipment such as cargo containers can be removed and lost or readily damaged, such parts will be removed, lost and/or damaged in the normal course of their use and that great difficulties and inconveniences will be experienced in maintaining such containers.
The construction of traditional cargo containers are made to comply with ISO standard 1496-1, which specifies dimensional and strength requirements but not construction methods. Cranes provided assistance for handling some loads and the advent of the fork lift truck led to the introduction of palletized loads which avoided handling of individual items when transferring between different types of transport at freight terminals. Palletized loads still offered limitations in relation to the speed of handling and especially in relation to their stacking capacity. This has led to development and widespread adoption of containers.
Various sizes have now become standardized 20′ (6 m) long containers are the most common. The width has become standardized at 2438 mm. Containers can be loaded at the source and are easily transferred between different types of transport e.g. road, rail or ship. Forklift trucks can be used to load a container with palletized loads. Pallets are approximately 48″×40″ (1200-1000 mm) square. Ten pallet places can be accommodated in a standard container. Large ocean going vessels have been designed for handling the containers which can be stacked one on top of the other perhaps as many as seven high. Containers have the advantage of offering protection to the contents within. There is a constant flow of containers around the globe to meet the requirements for the supply of raw materials and products. To maximize container utilization it is desirable to be able to fill a container whenever it is moved from one location to another, but it has been calculated that 20% of containers are transported empty on repositioning runs.
U.S. Pat. No. 8,783,489 proposes a shipping container that can collapse by having the end doors rotated upward to the ceiling of the empty container, and then having the side walls buckle inward to a collapsed configuration. However, there is not a satisfactory way to lock and unlock the collapsed doors and walls without using a mechanical spreader, and there are there is a need to be able to quickly and reliably lock and unlock the components in place without the need for a spreader apparatus. The present invention solves this need.